While I definetelly agree with everything that u said about the technical side of the game, I have to disagree with one thing. AC Unity stomps Witcher 3 when it comes to graphics. Even early WIP demos of Unity look way better than what we got in latest W3 demos. And im not talking just about visual quality - things like fluid animations and framerate, cloath physics, realistic colours, climbing/navigation, high level texturing - all are beyond Witcher 3.
It's way too early to compare AC Unity with the Witcher 3. The former releases in only two months, whilst the latter releases in 6 months. There's plenty of development time left for the Witcher 3, but AC Unity isn't likely to change much between now and release date..